How popular is Sondra?

Sondra is a very popular first name for females (#639 out of 4276, Top 15%) but a rare last name for both adults and children. (2000 U.S. Census)

Sondra entered the list in 1920-1929 and reached its highest position of #279 in the U.S. during 1940-1949, but is not found in the list currently. (2015 Birth Statistics)

Which version is better?

with its variant forms and related girl names. Popular alternative forms of Sondra rated in the Top 2000 are Alexandra(#101 in recent rankings), Cassandra(#511), Sandra(#831), Sandy(#1918), Zandra, Saundra, Sandie, Sandee and Sandi. Other forms, like Alandra, are uncommon. These relations of Sondra were popular as baby names 75 years ago (average #693) and are now much less popular (#1536, ▼92%), with forms like Sandra becoming somewhat outmoded.